SketchUp - Robert Lang
Tutorials, tips, tricks, and more about the 3D modeling software. Lang, a professional woodworker, cabinetmaker and designer who serves Popular Woodworking Magazine as its Executive Editor, uses SketchUp to design woodworking projects, and as the basis
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Skill in Algebra - Lawrence Spector
An introduction to algebra, with questions that, when moused over, reveal their answers: algebraic expressions, signed numbers, adding and subtracting signed numbers, multiplying and dividing signed numbers, reciprocals and zero, removing grouping symbols,
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Skydome Unit Plan - Ruth Carver, Margaret Sinclair
A unit suitable for grades 7-11 with the objectives: to review many different mathematical skills; to work on a unit that connects with the "real world"; to improve reading for information skills. Questions include: What is the lowest price for a seat
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Skymath National Weather Report Module
An overview of an instruction unit in which students produce a national weather report and a report on their understanding of various weather phenomena. The unit ties together number sense, symbols, and graphics; emphasizes sorting and counting and making
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Sliding Pi - Ivars Peterson (MathTrek)
"The entrance to the Downsview subway station in Toronto presents visitors with a striking vista. A vast mosaic of square tiles sweeps across a curved wall, inviting viewers to trace its lines and ponder intriguing irregularities
in its color scheme
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Slinky Science - National Engineers Week Committee
Classroom activities include Racing Slinkys, which describes how inertia, gravity, potential energy, kinetic energy, and longitudinal waves are demonstrated when the Slinky "walks" down stairs or an incline; Slinky Waves, which outlines how Slinkys exhibit
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Sloan Digital Sky Survey
The astronomical surveys of the Sloan Digital Sky Survey (SDSS) have "obtained deep, multi-color images covering more than a quarter of the sky and created 3-dimensional maps containing more than 930,000 galaxies and more than 120,000 quasars." SDSS's
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Slocum Puzzles - Jerry Slocum
Puzzle collector and author's site. Features puzzle descriptions, shop, descriptions of books written by Slocum and collaborators, and a history of Slocum's famous Puzzle Parties.
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Smartkiddies Mathematics - Andy Hobeika
Free interactive lessons, number challenge exercises, worksheets -- and visual reporting for instant feedback. To begin, select a year (one through seven, corresponding to Australia's curriculum), then a module, ranging from whole number to position &amp
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Smithsonian Institution
An independent trust instrumentality of the United States holding some 140 million artifacts and specimens in its trust for "the increase and diffusion of knowledge," and a center for research dedicated to public education, national service, and scholarship
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Smith's Stuff: Resources - Mark Smith
Mark Smith shares resources that he has created as a high school teacher: games, mnemonics, activities, sketches, and more. Sign up for a free account if you'd like to share activities here as well.
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Snow Day Calculator - David Sukhin
Enter a ZIP code and number of school days already canceled there due to inclement weather, and the Snow Day Calculator predicts the probability of an early dismissal or no school the following day. Sukhin originally developed his predictive calculator
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Snowdays - Popular Front
Make your own snowflakes online: point and click to cut anywhere around or inside the folded piece of virtual paper. Preview the unfolded results in real time; when ready, save your design to the searchable gallery, where you may view and download plans
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Snowflakes - Kenneth G. Libbrecht
"Your online guide to snowflakes, snow crystals, and other ice phenomena." Snow activities include instructions for using everday objects and dry ice to make your own snowflakes; for using glue to make plastic snowflake replicas ("snowflake fossils")
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Soap Bubbles - Ron Hipschman; The Exploratorium
Why does a bubble form a sphere? Why not a cube, tetrahedron, or other geometrical figure? This site from San Francisco's Exploratorium provides information on the shape of bubbles and what happens when bubbles meet, with formulas for long-life bubble
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Soap Films and Grid Walks - Ivars Peterson (MathLand)
A simple, physical demonstration of a mathematical truth can produce a lasting impression - one that inspires new questions and speculations. For Christopher C. Chang, a student at Henry M. Gunn Senior High School in Palo Alto, Calif., and one of 40 finalists
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Society of Actuaries
Actuaries are professionals trained in mathematics, statistics, and economic techniques that allow them to put a financial value on future events. This skill is of great value to insurance companies, investment firms, employee benefits consulting firms,
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Society of Young Mathematicians - SYMs
A UK organization that motivates and encourages "all young people who enjoy mathematics." SYMS publishes articles, news, "things to do," calculator hints, book reviews, games, puzzles, and competitions in its newsletter, SymmetryPlus, and termly journal,
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Soddy's Formula - Pat Ballew
Descartes' Circle Theorem, an example of giving the credit to the wrong person. The formula is about the relation of the radii of four mutually tangent circles and is sometimes called the Kissing Circles Theorem: if four circles are all tangent to each
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Sofist India - Sofist India
A software company that specializes in developing off-the-shelf products and components (assemblies) using Microsoft .NET technology. The company also develops and maintains software packages and develops web sites. Its expertise lies in the fields of
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Software by Al Jarnow - ProtoZone Interactives
Web-based interactive software excerpted from pattern exhibits at the Long
Island Children's Museum, the National Museum of Science and Industry (London),
and the Brooklyn Childrens's Museum. Introductions to art and math with many pattern-making
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